From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EA0E74ABBD7; Thu, 17 Sep 2026 15:46:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789660014; cv=none; b=DNrYGrUInM8mWmdiEJhbbi4qwvcapycG0dE+gShrJhChIzBaIbkzR4a05hE41aN1+wFzpdjH0gY7EhoJdDicR781fbv8pwMr2RYj/h9yNYXyuN32YQGJqUkcxl/hZvEucQCmecbFlj5QupNisbYQrBgwLnEFmnbWTCP/PvVG3bw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789660014; c=relaxed/simple; bh=UqmAr7XzwtM9nyPohbwmEsENGuedlLqRW9vzCoKUMQc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=eLqqQoYrrxslrM8u7aRC0N/XY9cRTkbHXPf99SqDrX4wghKwK8oZ4L9k4v/b6eRlo81JUm1azuATqFSBpiXeAXDMijMlTCNpj8avaG1uJofMBzfxo/JKM5GtzYj8R+4I0MDE4Zl3vTZLms/az/fKrHdjgSriko3Cv9wO71Fe9Ds= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=gGUznN32; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="gGUznN32" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 74C771F00898; Thu, 17 Sep 2026 15:46:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789660006; bh=OJxw/FlDFvD4XjVCOTLcLtGIOxRhPCgX0eAwqg5BU/M=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=gGUznN32X6Cp9JO3/CVBDzw31tShuYNbyoXhM7nTQQ9y62DpRtdXmidoD+QJYyAT6 l2RqCjdBh+inK7JmGLGAAF3THwNJgKypZvCjN/NU/dN5kG2GKAf4IrU2QKRI4sjfDc 2bCzTMAQDB+nxFLqnrC+i1K2jpnnUe7tJON83dM4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Vincent Donnefort , Steven Rostedt , Sasha Levin Subject: [PATCH 7.2 446/733] tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing Date: Thu, 17 Sep 2026 16:12:34 +0100 Message-ID: <20260917151403.002249625@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260917151350.597953846@linuxfoundation.org> References: <20260917151350.597953846@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Vincent Donnefort [ Upstream commit d059d8bf2c9b5d563d15e7552d73e17d7535013a ] The number of pages per remote ring buffer is capped by ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to overflow that field would silently allocate a descriptor smaller than what was asked for. Return SIZE_MAX from trace_buffer_desc_size() on nr_page_va overflow. Link: https://patch.msgid.link/20260911193937.602202-3-vdonnefort@google.com Fixes: 2e67fabd8b77 ("ring-buffer: Introduce ring-buffer remotes") Signed-off-by: Vincent Donnefort Signed-off-by: Steven Rostedt Signed-off-by: Sasha Levin --- include/linux/ring_buffer.h | 4 ++++ kernel/trace/trace_remote.c | 6 +++++- 2 files changed, 9 insertions(+), 1 deletion(-) diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h index 11bffb6a142d1..eac3e9080c3c0 100644 --- a/include/linux/ring_buffer.h +++ b/include/linux/ring_buffer.h @@ -295,6 +295,10 @@ static inline size_t trace_buffer_desc_size(size_t buffer_size, unsigned int nr_ unsigned long nr_pages = __calc_nr_pages_ring_buffer_desc(buffer_size); struct ring_buffer_desc *rbdesc; + /* Capped by ring_buffer_desc::nr_page_va */ + if (nr_pages > UINT_MAX) + return SIZE_MAX; + return size_add(offsetof(struct trace_buffer_desc, __data), size_mul(nr_cpus, struct_size(rbdesc, page_va, nr_pages))); } diff --git a/kernel/trace/trace_remote.c b/kernel/trace/trace_remote.c index 0e8ca62301040..c79cd21347a03 100644 --- a/kernel/trace/trace_remote.c +++ b/kernel/trace/trace_remote.c @@ -980,9 +980,12 @@ int trace_remote_alloc_buffer(struct trace_buffer_desc *desc, size_t desc_size, const struct cpumask *cpumask) { size_t min_desc_size = trace_buffer_desc_size(buffer_size, cpumask_weight(cpumask)); - unsigned int nr_pages = __calc_nr_pages_ring_buffer_desc(buffer_size); struct ring_buffer_desc *rb_desc; int cpu, ret = -ENOMEM; + unsigned int nr_pages; + + if (min_desc_size == SIZE_MAX) + return -E2BIG; if (desc_size < min_desc_size) return -EINVAL; @@ -991,6 +994,7 @@ int trace_remote_alloc_buffer(struct trace_buffer_desc *desc, size_t desc_size, desc->struct_len = min_desc_size; rb_desc = __first_ring_buffer_desc(desc); + nr_pages = __calc_nr_pages_ring_buffer_desc(buffer_size); for_each_cpu(cpu, cpumask) { unsigned int id; -- 2.53.0